Corpus Christi Bay thrives as shark breeding ground
A South Texas bay has become a thriving breeding ground for several species of sharks, marine researchers have learned.
From March to October, researchers with the Texas State Aquarium and Texas A&M University-corpus Christi caught and tagged sharks in Corpus Christi Bay.
“The study was an incredible success. We learned a lot in the field, not just about the sharks, but improved our field techniques,” Texas State Aquarium senior vice president Jesse Gilbert said.
Estuaries, such as Corpus Christi Bay, are commonly inhabited by elasmobranchs — sharks and rays — who go there to give birth. Pregnant sharks look for shallow areas along the coastline where there is plenty of food and shelter from larger predators.
Shark pups like the ones found in the bay are usually born up to 12 months after gestation, and a litter can have up to 30 sharks. They are left on their own after birth, staying in shallow water for about three years while they learn to hunt before swimming out to the larger ocean.
Historically, the bay was known as a critical habitat where pregnant sharks go to give birth, and researchers wanted to collect environmental data to learn how many sharks and which species use the bay.
Texas State Aquarium officials were approached by David Portnoy, a Texas A&m-corpus Christi associate professor of marine biology, to look at the sharks in the bay because there was little information about elasmobranchs there.
Researchers from the aquarium and A&m-corpus Christi went out every Wednesday to
tag, measure and collect DNA samples from the sharks before they were released back into the bay.
Researchers have tagged seven species of sharks and three species of rays.
“There were days they would call in (from the boat) with the numbers and we thought we had misheard what they said because the numbers were so high,” Gilbert said.
One major discovery is the presence of the smalltail shark, which was not found in the bay before. Gilbert said the researchers were “very surprised but in a good way” to see that the bay was thriving more than anticipated.
Despite the large populations of sharks, Gilbert said they pose little to no risk to humans as all the species found strictly eat fish and shrimp. Instead, the high number of sharks is beneficial for people, especially anglers, because it shows that the Corpus Christi Bay is a healthy, growing system with lots of fish.
Gilbert said the shark populations are also a testament to the Corpus Christi residents and visitors who work to help keep the bay clean. Every Texas State Aquarium visitor helped fund the shark project, as a portion of ticket sales goes to conservation research.
“This is really good news for us because a true value of being a Texan is a love for the outdoors, and having a bay that functions as a vital nursing habitat allows for people to be able to see sharks and fish in our environment,” Gilbert said.
This study opened the door for future projects by providing researchers a baseline for shark research in the bay. Gilbert said they are already looking at a similar study to do in about five years to see how the shark numbers have changed.